The invention pertains to an autarkic, self-supplying and self-sustaining monument in an aircraft pressure cabin that is supplied with the operating mediums required for its operation in a decentralized fashion by carrying along these operating mediums in the monument in operating medium reservoirs. The autarkic monument may be installed in the passenger area, as well as in the cargo compartment. The invention furthermore pertains to a method for the efficient energy conversion within the autarkic monument. According to the characteristics of this method, the energy conversion processes that take place in the monument and are based on the operating mediums carried along are optimized and adapted to one another with respect to exergetic, economic and ecologic aspects, i.e., with respect to exergo-economic and exergo-ecologic aspects.
In this context, exergo-economic and exergo-ecologic respectively mean a combination of economic or ecologic observation and exergy analysis. In contrast to conventional energy consumption analyses, the exergy analysis makes it possible to optimize a system in such a way that it has a minimal operating medium consumption with respect to its process function and optimally utilizes and converts energy forms present in the system.
Monuments are large integral components installed in an aircraft pressure cabin. These monuments include, for example, the galleys, rest compartments for the flight or cabin crew, bar and reception areas, installations for the on-board entertainment, as well as toilets, showers and lavatories. It is known that a monument of this type needs to be provided with a mechanical mounting device in order to install this monument in the cabin. This is usually realized on the seat rails in the floor, as well as on other mounting points provided in the aircraft fuselage for this purpose. In order to flexibly position the monument, its mounting is realized in a detachable fashion such that a fast and simple conversion of the cabin is ensured (DE 202008003772 U1, DE 602005006280 T2).
However, if operating mediums need to be supplied to the monument, the flexibility with respect to its positioning in the cabin is significantly limited because supply lines and connections cannot be planned, installed and connected to the monument with unrestricted flexibility. For example, a chain device for guiding an electric connecting cable (DE 102007003802 B4) represents one known approach for flexibly positioning a monument with operating medium supply.
It would also be conceivable to guide a data cable by means of such a chain device. A monument needs to be connected to data cables, for example, in order to control and parameterize its functions via the cabin network, as well as for transmitting and exchanging data and signals with other systems in the aircraft. A self-configuring radio network in the cabin (GB 2430118 A, WO 2005 120069 A2) represents one known approach for realizing a flexibilisation of the data link of a monument. In this case, the data is transmitted in a wireless fashion, for example, between a passenger service unit (PSU) or a router of the on-board entertainment system and a group of passenger seats such that groups of seats can be flexibly and freely configured with respect to their data link.
In the cabin of a modern passenger aircraft, electric energy represents an important and therefore preferred operating medium for supplying monuments because it can be easily generated, distributed in a nearly lossless fashion and converted into practically any other form of energy. The generation of electric energy takes place on the aircraft engine by means of a generator due to the conversion of shaft power into an electric current. The current is subsequently transported from the generator to be monuments in the cabin via a central main distributor and a distribution network.
In order to exploit the known advantages of utilizing electric energy as operating medium, namely the nearly lossless distribution and the simple optional conversions into other energy forms, a complex distribution network that originates at a central location and has a hierarchic structure is nowadays required in aircraft for this operating medium. The distribution in the network takes place in a cable-bound fashion and therefore allows only little flexibility. In addition, a thusly structured distribution network results in a high cable weight and high installation expenditures.
For example, one known approach that counteracts these negative effects is the utilization of the seat rails in the floor for the power supply of a monument mounted thereon (DE 102004039189 A1). In this case, an electric potential is applied to the seat rail by means of a conductor and can be tapped on the seat rail at any point with a second conductor. However, this approach does not make it possible to transmit an arbitrarily high power and the distribution network still originates at a central location.
Electric energy can also be transmitted to power consumers in a contactless fashion, but such a contactless transmission also does not provide any significant advantages in comparison with the known approaches that utilize a chain device (DE 102007003802 B4) or the seat rails (DE 102004039189 A1) because the contactless transmission link can only have a length of a few centimeters. Consequently, an advantageous flexibilisation of the operating medium supply cannot be achieved and the distribution network in this case also needs to originate at a central location and be organized hierarchically.
In addition to these disadvantages associated with the distribution of electric energy in aircraft, other disadvantages result from the fact that the entire energy conversion chain does not represent an efficient energy conversion process with respect to exergo-economic aspects, wherein this is elucidated with reference to the exemplary illustration in FIG. 4: in order to generate heat in a monument in an aircraft pressure cabin, the fuel kerosene is nowadays converted into shaft power in the engine and then converted into electric energy by means of a generator connected to the shaft. This electric energy is subsequently used 401 for generating heat, for example, in an oven. In this case, the energy conversion efficiency is primarily limited by the efficiency η of the engine that, according to the laws of thermodynamics, can maximally reach the theoretic Carnot efficiency ηc. The efficiencies are more favorable and a more efficient energy conversion results if electric energy is generated from a fuel, for example, by means of a fuel cell and subsequently converted 402 into heat.
For example, a galley monument is conventionally used in aircraft. This monument is not relevant for the safe and reliable operation of the aircraft and requires the largest amount of energy of all aircraft and cabin systems. This energy is supplied to the monument in the form of an electric current and occasionally also an additional operating medium in the form of a coolant for refrigeration purposes (DE 4340317 A1). One disadvantage of such an energy supply is that it requires correspondingly configured supply lines that cannot be flexibly planned and realized with respect to their distribution network architecture. Due to its high energy demand, this monument continues to disadvantageously influence the design of other aircraft components required for power generation and cooling purposes, as well as the corresponding distribution networks.
A method for making available energy and a supply unit designed in the form of a galley trolley or a luggage or cargo container were developed (WO 2009/046805 A1) in order to counteract this known disadvantage. Since this unit is equipped with a fuel cell including its fuel supplies, electric energy can be made available in a decentralized fashion. In this case, however, it is very disadvantageous that this electric energy is used for powering heating and/or cooling units in the next step. In terms of the energy conversion processes described above and illustrated in FIG. 4, a large portion of the chemical energy contained in the fuel remains unused in this method.
It therefore is the objective of the invention to realize an autarkic monument in such a way that it can operate in a self-sustaining fashion, wherein operating mediums to be carried along are chosen such that efficient energy conversion processes result for the functions of the monument to be fulfilled and/or that a high overall efficiency of the interlinked energy conversion processes results within the autarkic monument.